Novak Djokovic equalled Roger Federer's record for the most men's grand slam singles semi-final appearances in history by coming from a set down to defeat Andrey Rublev.The Serbian’s 4-6 6-1 6-4 6-3 victory on Centre Court sent him through to the last four at a major for the 46th time and extended his winning run at Wimbledon to 33 matches.Djokovic is now only two wins away from yet another grand slam title and, although this performance was not quite perfect, it was another demonstration of what it will take to stop the 36-year-old lifting the trophy for an eighth time.Rublev played a terrific match yet landed only a glancing blow on Djokovic, with the Russian now the first man in the open era to have lost his first eight slam quarter-finals.He is one of the hardest hitters in the game, particularly off his forehand, while his intensity has made him a favourite of Djokovic's five-year-old daughter Tara.Rublev lost in straight sets to Djokovic at the same stage of the Australian Open and he knew the importance of hanging with the defending champion, which he did by saving three break points in the sixth game.Winning is in his DNA#Wimbledon | @DjokerNole pic.twitter.com/iQKllpuArqThe pair were fighting fire with fire and Djokovic thrust his arm into the air after winning one particularly fierce exchange.He dropped his level at the end of the opening set, though, and Rublev capitalised, clinching a break point to lead 5-4 and then serving it out.It was the second set Djokovic had dropped in successive rounds after a wobble against Hubert Hurkacz but he responded in impressive fashion, racing into a 5-0 lead in the second set.If Rublev struggles to get to sleep, it may well be because of the third set, where he certainly